> go and collect some evidence then compare it to what the person is saying It's so much easier said than done though. Think about an example that might come u

> go and collect some evidence then compare it to what the person is saying It's so much easier said than done though. Think about an example that might come up in daily life. Say, someone says they're busy/absent/whatever at X time, but then you spot them at that time, very clearly to the contrary. Did they lie to you? Sure looks that way. But it could also be that their schedule just changed. How can you possibly tell? Either you have to do it repeatedly and look at it statistically, or go prying around or asking other people to vouch for their story, or you have to ask them directly. Are you willing to do that? Especially if it happens multiple times? What if they in fact didn't lie, but also feel it's an invasion of their privacy to have to give a compelling explanation of what happened? Or what if they did lie, but only due to circumstances beyond your imagination where you might have lied, too? Are you willing to risk your relationship with that person to make a determination?